The Role of RNA:
Making a Paper Model of Protein Synthesis
Class Set
Background
DNA is the nucleic acid that is responsible for storing a cell's genetic information in the form of coded
instructions. Because DNA does not leave the cell's nucleus, the instructions must be copied onto a messenger that
can bring the genetic information from the nucleus to the ribosomes. Once here, the ribosomes make proteins, which
control the biochemical pathways within the cell.
The nucleic acid that is responsible for performing these functions is RNA. RNA consists of a single chain of
nucleotides. Each nucleotide contains a 5-carbon sugar (ribose), a phosphate group, and one of the following
nitrogenous bases: guanine (G), cytosine (C), adenine (A), or uracil (U).
Although a cell contains many different forms of RNA, there are three main types that are involved in
expressing the genetic code. The three main types of RNA are messenger RNA (mRNA), transfer RNA (tRNA), and
ribosomal RNA (rRNA). The process of transferring the genetic information from DNA to mRNA is called
transcription. The process that decodes mRNA into a protein is known as translation.
Procedure:
Part I Transcription: Below is a segment of
Transcribe the DNA into mRNA.
DNA Strand A: AGT GTT GCT
DNA Strand B: TCA CAA CGA
mRNA: ____ ____ ____
1. Demonstrate what occurs in step one
of protein synthesis by drawing the
site of transcription, writing down
the DNA and gluing the resulting
mRNA copy beneath.
2. Make sure to label the nucleus,
DNA, mRNA and show the
movement of mRNA after
transcription.
3. Color the inside of your nucleus.
DNA.
Transcription Analysis: Please label this
on the back of your colored paper
1. Copy the mRNA strand onto your colored paper.
2. Which DNA strand is being transcribed? How do you know?
section
Part II Translation:
1. Color your second set of mRNA nucleotides, tRNA molecules and amino acids.
2. Cut out the pieces, they will be used to model translation.
a. ONLY CUT ALONG SOLID LINES!!!
3. Graphically demonstrate the process of translation in protein synthesis. You will need to draw the ribosome (site
of protein synthesis), showing how the mRNA strand moves through the ribosome.
a. Show the direction of translation with an arrow along the mRNA strand.
4. Arrange your mRNA nucleotides on the bottom of your paper, feeding through the ribosome.
a. Make sure the order is consistent with what was transcribed in the nucleus!
5. Use your tRNA molecules to demonstrate the following three events:
a. One tRNA should be actively translated (label this as “being translated”), and the amino acid should be
separating from the tRNA to the polypeptide chain.
b. One tRNA will have already been translated and should be labeled as “leaving the mRNA”
c. The third tRNA should still be in the cytoplasm, but is arriving onto the mRNA strand to be translated
next. Label and show this movement.
6. Review the grading rubric and label any remaining aspects of the protein synthesis process.
Translation Analysis: Answer in complete sentences on the back of your poster. Label section!
1. Describe the function of tRNA after it leaves the mRNA strand.
2. What is the difference between the role of mRNA and the role of tRNA?
3. What is a pepide bond? Using your knowledge from organic compounds (think wayyyy back to Chp.2!) how does
the peptide bond form? (think back to the protein ID activity with amino acids)
4. What is the role of the anti-codon in translation? Why is it important to protein synthesis?
5. Compare and contrast the two steps of protein synthesis. Cite two comparisons, and three differences.
Role of RNA: Grading Rubric
 +1 pt: Title “Role of RNA” clearly written at top of page
 +8 pts: The following are labeled: nucleus, cytoplasm, ribosome, transcription,
translation, peptide bond, mRNA, rRNA, tRNA
 +3 pts: Labeled: tRNA entering mRNA. tRNA being translated, tRNA leaving
mRNA
 +2 pts: mRNA strand in nucleus in the following order:
AUG UAA CCG CGC AAU GCG UUA GAU
 +3 pts: Verify the correct tRNA is near the matching mRNA:
tRNA with GCU should be near mRNA CGA
tRNA with AGU should be near mRNA UCA
tRNA with GUU should be near mRNA CAA
 +2 pts: Poster has good use of colors and is organized and easy to interpret.
 +2 pts: Poster has good use of colors and is organized and easy to interpret.
 +6 pts: Correctly answered questions on the back of the poster.
Total Points Possible: 20